United Launch Alliance has set Friday, November 13 for Vulcan’s return to flight, nine months after a solid rocket booster nozzle failed during the rocket’s fourth launch. The mission, called Vulcan Leo 1, will carry 40 Amazon Leo internet satellites from Florida. It is also the first Vulcan flight with six strap-on boosters.
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The date is a target announced on October 28, and ULA has not published a launch time. The booster fix flying on it is what the Space Force is waiting to see.
Two nozzle failures on the Northrop Grumman boosters
Vulcan flies with Graphite Epoxy Motor 63XL boosters built by Northrop Grumman, and their nozzles have now failed twice. According to Spaceflight Now, a nozzle disintegrated on one of the two boosters during the second flight. A similar failure hit one of four boosters shortly after liftoff on February 12, 2026, during the USSF-87 mission for the Space Force. In both cases the upper stages compensated for the asymmetric thrust and reached the intended orbits, so no payload was lost. The rocket has not flown since. Spaceflight Now counts the coming mission as Vulcan’s fifth flight since its 2024 debut, and the investigation team of ULA, Northrop Grumman and the Space Force has not released specific findings.
The February event also hit the supplier’s books. Northrop Grumman’s first-quarter earnings release cites a $71 million unfavorable adjustment on GEM 63XL tied to a launch anomaly in the quarter, which the blog Behind the Black connected to the Vulcan boosters. That blog adds that ULA first called the February event an observation before upgrading it to a significant performance anomaly, and that the grounding reaches Amazon’s own Leo launch plans.
The redesigned nozzle and what ULA has said about it
ULA says a team drawn from the company, Northrop Grumman and the Space Force identified several potential contributors to the anomaly and mitigated them through nozzle design and process changes. It has not released specific findings. In a statement carried by Air & Space Forces Magazine, the company said that to support its customers, the upcoming launch will use the improved nozzle design, with additional testing and analysis continuing in parallel with the mission.
Northrop Grumman test-fired a 63XL motor on April 15. A ULA spokesperson told Spaceflight Now the test was meant to demonstrate nozzle enhancements already in work, and that its data would validate analytical models and support the return to flight. The company also says that by flying the new design it gains flight data to confirm the changes, which is a candid admission that the fix is still being proven.
Several things remain unannounced: a launch time, any root-cause findings and what the Space Force still requires before trusting Vulcan with national security payloads. Spaceflight Now asked the service what work remains and printed no response. ULA says additional testing and analysis continue in parallel with the mission, so the November 13 flight doubles as a data-gathering flight for the nozzle, not only a delivery run for Amazon.
Amazon’s cargo and the military payloads left waiting
The 40 satellites are a meaningful batch for Amazon. Spaceflight Now reports nearly 400 Leo satellites are already in orbit, that Amazon has booked 38 Vulcan launches, and that earlier Leo missions flew on Atlas V, Ariane 6 and Falcon 9. The fairing holding the satellites left Amazon’s processing facility on October 21, and a second Vulcan for Leo 2 is already stacked in ULA’s original integration facility. This stack was assembled in Amazon’s new Vertical Integration Facility at Cape Canaveral Space Force Station and rolled out for fueling tests in August.
The satellites will separate from an adapter on the Centaur upper stage over about half an hour. Vulcan can carry more Leo satellites than any rocket except Blue Origin’s New Glenn, and a New Glenn intended for Leo was destroyed in a pad explosion in May during a test fire, with no satellites aboard.
Government customers have been rerouted in the meantime. Space Systems Command moved the final GPS III satellite to a Falcon 9 in April, shifted an Oracle-M cislunar pathfinder to Falcon Heavy, and moved a Next-Generation OPIR missile warning satellite from Vulcan’s USSF-50 to USSF-174 on Falcon Heavy, according to Air & Space Forces Magazine. The magazine adds that the grounding delayed the first Next-Generation OPIR launch, that ULA and SpaceX are the only two providers certified for the most sensitive national security missions, and that for full swaps the Space Force will move a future SpaceX mission back to ULA later instead of canceling ULA contracts.
Brig. Gen. Eric Zarybnisky, the Space Force’s portfolio acquisition executive for space access, told reporters on October 21 that his team is actively working with ULA and is weighing how much risk it will accept on some key missions. He stressed that some missions cannot easily change rockets because of integration timelines and technical constraints. He said it is unclear when Vulcan will carry military payloads again, and that the service will use data from the first few commercial flights to plan. A clean November 13 mission would give him the first piece of that data.
This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.
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